While wall-forming systems have been in use for many years, a recent development in this industry is in the use of polystyrene panels as forms for poured concrete walls. After the concrete has hardened, the panels remain in place on the walls to serve as permanent insulation. One example of this recent development may be found in U.S. Pat. No. 4,706,429 entitled "Permanent Nonremovable Insulating Type Concrete Wall Forming Structure."
This new wall-forming system utilizes a system of "blocks," each block comprising a pair of polystyrene panels connected in parallel, spaced-apart alignment by a series of rigid synthetic plastic ties between the panels. Each panel has a series of T-shaped slots along its upper and lower edges, into which T-shaped ends on the plastic ties are inserted to "lock" the panels in spaced-apart relation. The upper and lower edges of the panels have castellations which further serve to lock the panels in vertical and horizontal relationship. The end edges of each panel have dovetail type tongue and groove joints to allow for slidable interconnection. The interior face of each of the panels is striated so as to allow modular end panels to be slidably located between the wall panels at any given location, and to promote adhesion between the panels and concrete.
Once concrete is poured between the panels, the concrete will adhere to the striations on the panels and hold the panel in place. Since the T-shaped ends of the ties do not extend completely through the panels, a smooth panel surface on the exterior of the wall could be finished as desired. It can be seen that the panels of the prior art provide a form for pouring the concrete, as well as insulating the wall once the concrete has hardened.
While this nonremovable insulated concrete form system has advantages over the prior art, the system is limited by the fact that the panels are permanently adhered to the concrete wall. Thus, such a system is not capable of use on those occasions where an exposed concrete surface is desired. On those occasions, it was necessary to revert to the older methods of wood form boards, steel bracing within the concrete, and extensive exterior bracing to hold the form boards in the appropriate alignment. Such a system is cumbersome, utilizes heavy material, and is difficult to utilize to produce accurately aligned walls. Furthermore, the materials of old methods of forming concrete walls must be moved from site to site, thereby requiring storage facilities.
A further problem with the prior art form systems is in the fact that each of the panels requires significant machining in order to create the tongue and groove portions, the striations, and the castellations in order to lock the panels together. This can significantly increase the cost of the panels because of time and material spent. Furthermore, use of castellations on the panels forms small portions which are easily broken off the panels during construction. This leaves unsightly holes and pockmarks in the face of the finished wall.
Another problem with prior art form systems is in the large number of ties which must be utilized in order to hold the panels in spaced-apart relationship. For instance, the system disclosed in U.S. Pat. No. 4,706,429 requires a series of ties spaced intermittently along both the top and bottom edges of every panel. Since the ties are not evenly spaced vertically and horizontally, conventionally dimensioned coverings are not conveniently attached to the ties through the panel surface.
A further problem with prior art concrete forming systems is in the fact that the height dimension of the panels limits the width of the wall which may be poured. Typically, conventional panels have a height of approximately 12 inches, and are useful in forming walls of less than 12 to 14 inches. Attempts to pour walls thicker than 14 inches result in bulging of the panels between the vertically spaced horizontal edges.
Finally, as mentioned above, prior art forming systems utilized panels which were permanently mounted to the wall. This was partly due to the system of incorporating the ties into each panel, and partially due to the specific configuration of the panels themselves. In any case, the option to be able to remove the panels from the wall is a much desired advantage, and was heretofore unknown.
It is therefore a general object of the present invention to provide an improved concrete wall forming system.
Another object of the present invention is to provide a wall form system including pairs of oppositely disposed polystyrene panels, at least one of the panels being removable from the wall once the wall has been formed.
Still another object of the present invention is to provide an improved tie for use in the concrete wall forming system of this invention.
Still another object is to provide polystyrene panels for an improved concrete forming system which do not require complex machining.
Yet another object of the present invention is to provide a wall form system capable of forming exceptionally thick walls.
A further object is to provide an improved wall form system in which panels may be removed and used again.
Still a further object of the present invention is to provide an improved wall tie for a wall forming system which will allow direct connection of walers.
Another object of the present invention is to provide an improved method for forming a poured concrete wall.
Yet another object is to provide a method for forming a concrete wall with at least one surface of the wall exposed.
These and other objects will be apparent to those skilled in the art.